Current lack of understanding of the pathogenesis of herpes simplex virus (HSV)-induced stromal disease has limited the development of therapy for this significant clinical problem. The major objective of our studies is to characterize biochemical and physiological changes which occur in the cornea during HSV- induced disciform edema and necrotizing stromal keratitis. We will assess the status of the corneal endothelium, evaluating barrier function by measuring the transcorneal flux of dextran and inulin at various stages of disease. Specific ouabain binding capacity of the endothelium will be assessed as a measure of ability to pump ions and thereby limit the accumulation of fluid in the cornea. Data from these studies will help determine the nature of the endothelial damage which results in corneal edema and opacification. Computer-assisted analysis of photographs of alizarin red stained endothelial cell layers will be used to determine if the functional changes observed are due to loss of these cells from the cornea. Damage in the corneal stroma will be evaluated by measuring synthesis and depletion of glucosaminoglycans and collagen which play an integral role in maintenance of corneal clarity. We will assess the synthesis of these macromolecules in corneas at key stages of HSV-induced disease by in vitro pulse labeling with radiolabeled precursors. The appearance of radioactive degradation products in medium following the labeling procedure will be used to measure degradation of newly synthesized molecules. High performance liquid chromatography will be used to identify synthesis and degradation products. The role of replicating virus and viral antigen in the pathogenesis of disease will be evaluated by virus isolation and newly devised immunoperoxidase techniques, the latter allowing detection of viral antigen in intact corneal endothelium. An additional aim of this study will be to assess the effects of therapy with acyclovir alone or in combination with corticosteroids on development of disease, endothelial function, and the synthesis of macromolecules in the stroma. Data obtained from the proposed studies will increase our understanding of the pathogenesis of HSV-induced disease and the development of new forms of therapy.